Landfill gas collection efficiency: Categorization of data from existing in-situ measurements.

Landfill methane emissions are commonly estimated using cover-type dependent default collection efficiency values, with a first-order decay model or measured gas collection. Current default collection efficiencies used in the United States were predominately derived from 4 studies conducted during or prior to 2007 that relied on flux chambers. Flux chambers are limited by small sample sizes, placement restrictions, and the inability to measure emissions from gas or leachate collection systems.

Comparison of spinal curvature parameters as determined by the ZEBRIS spine examination method and the Cobb method in children with scoliosis.

Background And Purpose: The most common and gold standard method to diagnose and follow-up on scoliosis treatment is to capture biplanar X-ray images and then use these to determine the sagittal frontal spinal curvature angles by the Cobb method. Reducing exposure to radiation is an important aspect for consideration, especially regarding children. The ZEBRIS spinal examination method is an external, non-invasive measurement method that uses an ultrasound-based motion analysis system.

Reliability analysis of a sensitive and independent stabilometry parameter set.

Recent studies have suggested reduced independent and sensitive parameter sets for stabilometry measurements based on correlation and variance analyses. However, the reliability of these recommended parameter sets has not been studied in the literature or not in every stance type used in stabilometry assessments, for example, single leg stances. The goal of this study is to evaluate the test-retest reliability of different time-based and frequency-based parameters that are calculated from the center of pressure (CoP) during bipedal and single leg stance for 30- and 60-second measurement intervals.

The assessment of the spinal curvatures in the sagittal plane of children using an ultrasound-based motion analysing system.

In children's posture examinations the question often arises whether an X-ray examination is necessary or appropriate. On screening and in other cases when X-ray is contraindicated, alternative-non-invasive-examinations are available. To measure the shapes of the children's spines beside the Spinal Mouse also the Zebris ultrasound-based spine measuring instrument is accessible and nowadays commonly used.